Metal pipe



Aug. 3,' 1937.

J. D. SAMPLE METAL PI PE Filed Jan. 16, 1935 2 Sheets-Sheet l Aug. 3,1937. J. D. SAMPLE 2,088,763

METAL PIPE Filed Jan. 16, 1935 2 Sheets-Sheet 2 Patented Aug. 3, 1937PATENT orgies,

mm ms James D. Sample;

Birmingham, Ala, assignor 'to 1 McWane Oat Iron Pipe 60., Birmingham,Ala. Application 16, 1935, Serial ,No. 2,110

2' Claims. (01. 138-47) This invention relates to new and usefulimprovements in metal pipesr Heretofore, it has, been the practice'toform cast iron pipes with threaded ends which necg essarily reduced thestrength of said ends. Orig: inally these pipes were of uniformdiameters throughout their lengths, and as a result of contraction anddifferent strains and stresses and combination of these factors, thepipes would 10 often break at the inner end of the threads. Thiscondition was corrected by increasing the stockat the threaded ends ofthe pipe to'thereby provide either an increased exterior diameter ,or adecreased interior diameter to said ends. However, a pipe having anincreased diameter at its ends was not suitable for use with fittings,hav-,

ing nominal size threads; a pipe having a decreased interiordiameterthroughout the entire length necessarily reduced the carrying capacityof the pipe, and the additional, metal employed in both formsnecessarily increased the cost of manufacture a corresponding amount.

It is, therefore, the principal object of the present invention toprovide a cast metal pipe having uniform exterior and interior diametersthroughout its length and constructed in such a manner that the pipewill better resist breaking at either or both of its threaded ends.

Another object of' the, invention is to provide a cast metal pipe havinga body of ordinary strength, and relatively higher strength end sectionor sections, the latter receiving the threads which terminate at pointsin spaced relation to the unions between the body and the end sectionswhereby the points of strains will be located in spaced relation to theinner ends of the threads.

With these and other objects in view which will more fully appear, thenature of the invention will be more clearly understood by following thedescription, the appended claims, and the several views illustrated inthe accompanying drawings.

In the drawings:-

Flgure 1 is a longitudinal section showing a nonthreaded cast metal pipeconstructed in accordance with my invention,

Figure 2 is a similar view pipe with threaded ends,

Figure 3 is a front elevation of the apparatus employed in carrying outmy process of casting the pipe shown in Figure 1,

Figure 4 is a top plan view thereof, and

Figure 5 is an end elevation of the same, the 55 mold being shown insection.

but showing the metal such as an alloy of cast iron,-

' consists of the usual cope I ll reference numerals designatecorrespomi-v '1 in Dartsthroughout the several figures of the drawings.7

Reierringi to the accompanying drawings, my. improved castmetal pipe Ais shown in Figure, 2, wherein the pipe isor uniform exterior andinterior diameters throughout its entire length. The pipe includesarelatively long body section is and relatively short end sections 6. 6;l The body sectlonis formed of ordinary strength metal 10 such as castiron and either or both end sections are formed of, relatively higherstrength alloy with molybdenum and/or chromium. However,-itwill beunderstood that theseend sections may be formed 15 from any one oranycombination of the following metals with cast iron:

Molybdenum Chromium Nickel Titanium Zirconium It will be understood,that either or both end sections may be formed of relatively higherstrength metal than the body. After the pipe has been thus formed bycasting, the end sections are then formed with exterior threads I, 1,the inner ends 8, l of said threads terminating in spaced relation tothe points of union 9, 9,

between the end sections 6, 6 and the body section I. v a

My improved pipe is cast by the following processz-A horizontal mold Bis provided which and drag H. Supported within the mold are twopipecores ii, I 2 which are supported horizontally in the usual mannerand leading to these cores and to the mold cavity is a plurality ofspaced gates it, there being one of these gates for each end section 6of the pipe, and a plurality of these gates for the body section 5 ofthe pipe. These gates are preferably spaced apart at substantially equaldistances. A ladle C is associated with the mold and this ladle isprovided with a plurality of pour lips I 4, there being as many lips asgates, and the lips being arranged in register therewith. The ladle Cincludes the usual side walls I5, l6 and end walls l1, IT. The ladle,however, is divided by means of partitions l8, l8 into threecompartments consisting of end compartments l9, l9 and a centralcompartment 20. The num her of end compartments, however, is dependentupon the casting of either one or both ends of higher strength alloymetal. The end pouring end compartments though points of union are shownin are 2. between the alloy metalswill' be located at points substan'strength metal or iron flows from the interme,--

diate lips ll simultaneously and at substantially the same rates intothe intermediate gates i8, and the higher strength alloy flows from theend lips H, it simultaneously vand-at tially the same rate into the endgates ll, l3 causing the levels of gether. By reason of spacedapproximately equidistantly apart, the molten metal will be distributedevenly and will 0! course in opposite directions, and consequentlythepoints of union 9, I as shown mugordinary and higher strength tiallyintermediate the outer pairs of lips M.- Althe' drawings in order toindicate-that the end portion is constituted -diflerently from thebodyportion,

lt-willbeunderstood that there is no clearly -de-- fined or sharp lineof demarcation between the metals'oi the two portions. since the'moltenmetal in the body portion will be in contact with the molten metal inthe end portionwhen the is being cast. Consequently, tionwill merge withthe body portion, the metal in'the merging ends of said portionscomprising an intermixture oi body portion metal and end 40 portionmetal.

After the casting has been removed from the ner--sufllcient strength issectionsv whereby liability of breaking due to conthe two i'ne'tals torise'tothe gates it. "being the end por-' mold and cooled, one or bothend sections 8 are then provided with exterior threads 1, the inner endsof said threads terminating in spaced relation to the points of union 9between the ordinary and higher strength alloy metals.

From the foregoing, it will be observed that I have provided a bi-metalcast pipe with threaded end sections formed of higher strength alloymetal than the body section; that the points of union betweenthese'metals are located in spaced relation to the inner-endsfoi" the'threaded ends; that the pipe exterior and interior diameters throughoutits length; that by constructing a pipe in this manirnparted to the endtraction or'various strains and stresses will be reduced to a minimum;and the strength of one or both end sections after threading is closelycomparable to the strength of the body.

Iclaim:-- v y 1-. A pipe of cast metal comprising a body portion and athreaded end portion'me'rging there:- with; the end portion "comprisingalloy 'rnetal which is relatively st'ronger than themeta'l com thusformed is of uniform prising the body portion, the metal in the merg ingends of said portionscomprising inter mixture of the metal of the bodyportion amine metal of the end'porti'on. r 2. A'pipe-of castmetalcomprising a body per tion and a threaded end portion merging-therewith, the end portion comprising alloy metal which'is relativelystronger than the metal comprising thc body'portion, the metal in 'themerg'-= ingends oi said portions comprising an'intermixture of the metalof the bodyportion' and p the metal oi'the end portion; said portionshaving a substantially uniform diameter through-q out their lengths,

JAMES n. SAMPLE.

